The eyes of a betta fish are similar to human eyes in the respect that they don’t reflect light, which means they can’t see in the dark. In terms of more in-depth comparison, Betta Fish have decent eyesight and don’t have any trouble focusing on objects.
Betta fish are pretty near-sighted and have trouble focusing on things more than 2 to 4 feet away. They can recognize larger shapes and highly contrasted colors up to 10 to 15 feet away. They do have monocular vision, which means that they can see a different thing with each eye.
Since their eyes are posted on either side of their head, monocular vision certainly makes sense. There are plenty of animals in the world that are in the same weight class as a Betta fish, that have pretty poor vision and the Betta fish shouldn’t be lumped into the same category with them.
The fact is, for a fish, a Betta can see pretty decent if a bit shortsighted, but is that all there is to it?
Betta Fish Eyesight
Having eyes on either side of your head is a difficult concept to measure out in our brains. Human eyes combine two images into a single image with depth and color, however, the Betta doesn’t have that luxury.
Since their eyes are on either side of their heads, Betta fish cannot combine a single image, which is how we perceive depth. If you pull a pair of night-vision goggles down and over your eyes, it will give you an idea of how Betta fish see, from the perspective of a single eye.
Night vision goggles separate the individual eye’s ability to coordinate with the other eye, eliminating the sense of depth that we are used to. With Betta, it’s the same way, except their eyes capture different images and process them simultaneously, something our eyes don’t do.
With far more cones than rods, Betta Fish have diurnal retinas, which means that they are more than capable of seeing color. How well they see color, especially in comparison with humans, isn’t entirely clear.
What we do know is that Betta fish are capable of distinguishing between different colors. However, they need a great deal of light to do so. In a darker room with perhaps the only source of light in the aquarium, it may be more difficult for them to make those distinctions.
Bettas are also capable of making out shapes in well-lit environments. So shapes and colors are certainly not a handicap for Bettas, but neither are the primary methods in which Bettas sense things within their environment.
Do Betta Fish Use Other Senses?
As is true with many animals, a Betta’s other senses are the primary means by which they move about their aquatic world. Taste, smell, and hearing are three senses that far exceed the capabilities of a Betta’s eyesight.
Betta fish combine all three senses and use them as a single unit, which is why your Betta knows that a tiny piece of fish food just hit the water clear across and on the other side of the tank.
It’s not because the Betta saw the food, but because the Betta heard, tasted, and smelled the food the moment it hit the water.
Our hearing consists of what are termed, the stirrup, hammer, anvil, drum, etc. Betta fish have strikingly similar mechanisms, however, theirs are fine-tuned to a degree in which it gives them such a profound sensitivity that we can’t achieve naturally.
These “internal ears” can hear things dropped in the water. If you’ve ever looked closely at the tiny line that runs the length of your Betta’s body, you will discover that it’s not just a decorative line, but another method in which the Betta interacts with its environment, and it is perfectly in tune with the Betta’s hearing.
This “lateral” line is not a line at all but a series of pits that are motion-sensitive and pressure-sensitive cells. Not only does the Betta hear the food hit the water, but it also feels it, regardless of how far from the food it is.
Combined with its premium sense of smell and taste, a Betta has no problem navigating its environment and finding food. Obstacles and light or dark make little difference in terms of these capabilities.
Do Betta Fish Prefer Being in the Dark?
They don’t necessarily prefer it, but they would certainly appreciate a regular day and night cycle as Betta fish sleep better in the darkness, just like we do. It goes to show that bright lights penetrate their eyes just like ours.
It makes it hard for them to sleep well just as we would have a tough time closing our eyes and going to sleep in open sunlight, directly facing the sun. It’s easy to think of a fish as just a fish, however, imagine having to sleep like that, day and night, with a constant flood of light in your eyes.
Give your Betta a day and night cycle if at all possible. If your tank has adjustable LEDs, then you should turn them down to their dimmest settings if at all possible. Your Betta will thank you for it as it will be a much happier and healthier fish.
Do Betta Fish Recognize Their Owners?
Betta fish recognize their owner and it’s all thanks to their eyesight. Standing outside of an aquarium leaves the Betta with only one method in which to sense you and that is through eyesight.
If your Betta always visibly reacts when you come into the room, especially during what is normally feeding or playtime, then you can plan out your next visit to test its seeing capability.
Enter the room from the point farthest away from your tank and approach slowly until your Betta fish visibly reacts. You’ll get an approximation of how far away your Betta can both see and recognize you.
While Betta fish are shortsighted fish, it doesn’t mean that’s their only sense and they make up a lot of ground with all of their other exceptional senses. However, nearsighted doesn’t mean blind and a Betta can see pretty well over short distances.